Xenopus laevis has been a valuable model system for studying neural development. In more recent years its utility has been eclipsed by other model systems simply because it lacks the genetic tools required for molecular and cellular manipulations. Nevertheless, many features make Xenopus a unique and irreplaceable model for studying, manipulating and testing neuronal developmental paradigms in vivo. The focus of the proposed studies is threefold: 1) to provide the Xenopus community with much needed genetic information on the sequence and expression of gene transcripts and microRNAs in several regions of the X. laevis brain, in several identified neural cell types and at several developmental stages, 2) to generate reagents for molecular/genetic manipulations of identified transcripts and signaling pathways, including antisense morpholino constructs, siRNA and cell-type specific expression of genes of interest and 3) to use the reagents to probe the function of candidate regulatory genes in neurogenesis in the intact animal. The proposed work will generate a wealth of reagents that will significantly enhance use of Xenopus as an experimental model for biomedical research and permit cross-species comparative studies that will enrich research in other experimental systems.